Family

Fabaceae

Distribution

Occurs in tropical N.T. and W.A., N of 17º30'S.

Description

Shrub to 3 m high, spreading, resinous. Bark smooth, dark grey. Branchlets angular to almost flattened, red-brown or light brown, glabrous or occasionally puberulous; ridges resin-crenulated. Phyllodes narrowly elliptic or rarely ±oblanceolate, straight or slightly curved, (2.5–) 4–7 (–9) cm long, 6–18 (–28) mm wide, slightly oblique at base, with a small knob-like mucro at apex, with slightly undulate margins, ±glabrous, with 3 prominent longitudinal nerves reaching base and 2–4 subprominent parallel nerves; minor nerves 4–6 (–8) per mm, rarely anastomosing or indistinct from fine longitudinal wrinkling when dry; gland 1, ±conspicuous, basal. Spikes 1.5–5 cm long, bright lemon-yellow. Flowers widely spaced, 5‑merous; calyx 0.5–0.75 mm long, cupular, dissected by less than 1/5, glabrous; corolla 0.8–1.3 mm long, dissected to 1/2–2/3, with petals with prominent midrib; ovary glabrous. Pods narrowly oblanceolate, basally narrowed, flat, 2.8–7.2 cm long, 4–8 mm wide, crustaceous to thinly woody, brown, paler over seeds, obliquely reticulate, glabrous, opening elastically from apex; margins and seed-partitions thick. Seeds oblique, broadly oblong-elliptic, 4–6 mm long, brown or dark brown; areole open, depressed, dark brown; funicle-aril narrowly conical.

Phenology

Flowers Feb., May & June.

Habitat

Grows in stony, skeletal, sandy soils over laterite, sandstone, quartzite or granite, in monsoon forest along the coast or on the ranges in savannah grassland or eucalypt woodland.

Specimens

W.A.: near Wren Gorge, M.Hancock 506 (CANB, NSW, PERTH); 6 miles [9.7 km] W of Inglis Gap, Leopold Ra., I.V.Newman 640 (NSW); Lennard R. Falls, King Leopold Ra., W Kimberleys, 22 July 1974, J.H.Willis (MEL, NSW). N.T.: Victoria R., F.Mueller (MEL27245); Stuart Hwy, c. 29 miles [46.4 km] NW of Katherine, L.Adams 864 (CANB, NSW).

Notes

A member of the tropical Australian ‘A. stigmatophylla group’ which also includes the spicate inflorescence species A. cataractae, A. calligera, A. wickhamii and possibly A. oncinocarpa, A. drepanocarpa and other species, along with taxa with capitula, including A. anserina, A. delicatula, A. manipularis, A. nuperrima, A. perpusilla A. producta, Acacia sp. Kununurra (G.Lullfitz 6195), A. stellaticeps, A. translucens, A. setulifera, A. subternata and A. yirrkallensis. This group links sect. Juliflorae with sect. Plurinerves, and is characterised by being mostly resinous shrubs having branchlets with minutely resin-crenulated ridges, phyllodes with numerous closely spaced, slightly anastomosing longitudinal nerves (1–3 main nerves), flowers 5‑merous, petals with a midrib, and legumes being narrowly oblanceolate tapering gradually to base, opening elastically from a hooked apex, with woody flat valves with oblique nerves and prominent margins on the outer surface and partitions between the seeds on the inner surface, fide M.D.Tindale, Telopea 2: (1980).

FOA Reference

Data derived from Flora of Australia Volumes 11A (2001), 11B (2001) and 12 (1998), products of ABRS, ©Commonwealth of Australia

Author

Minor edits by B.R.Maslin & J.Rogers

Dr M.D.Tindale and Dr P.G.Kodela with the assistance of M.Bedward, S.J.Davies, C.Herscovitch, D.A.Keith and/or D.A.Morrison